Resembling the classic American skyscrapers of the early 20th century with a stepped design similar to Batman’s Gotham City, 40 Leadenhall Street is a truly iconic London project. It is one of the biggest schemes to have received planning permission in the city.
The scale and location among high-rise and historic buildings was challenging with a 3-level part top-down basement and two large cores rising to levels 37 and 17 constructed with SCP rigs. Significant 3D modelling of the cores was undertaken to ensure stability during the various construction stages of the core and to accelerate core construction.
The 37-storey north core was founded on a 2.5m deep, 1,500m³ waterproof reinforced concrete pile cap cast in a single operation over 6.5 hours – one of the project’s most critical structural elements. Before casting, we specified a thermal control strategy comprising a low heat concrete mix, analysis of the early age thermal performance of the proposed concrete mix, crack control reinforcement and thermal monitoring with appropriate control limits.
